Electrical signal system.



wwwtos PATENTED MAR. 6, 1906.

P. LAGRQIX. ELEGTRIML SIGNAL SYSTEM.

APPLIGATIGN FILI-3D AUILBQ, i904. BEBWED JULY 31, 1905.

UNITED STATES PATENT OFFICE.

FRED LACROIX, OF SAN ANTONIO, TEXAS, ASSIGNOR OF ONE-HALF TO OTTO KOEHLER, OF SAN ANTONIO, TEXAS.

ELECTRICAL SIGNAL SYSTEM Bpocication of Lettere Patent.

Patented March '6, 1996.

To @ZZ whom it may concern:

Be it known that I, FRED Laoaorinsd citizen of the United States, and a resident of San Antonio, in the county of Bexar and State of Texas, `have invented certain new and useful Improvements in Electrical Si al Slystems, of which the following is a. 31] c ear, and exact description, such as enable those skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawing, form;- in a part of this specication,

he invention relates to improvements in electrical s stems whereby the osition of a train anywhere between the en s of a 'track can be ascertained at either terminal,

In carrying out the' invention a normally open electrical circuit is provided whichwil be closed by a conductor, such as the wheels and axle of a locomotive, electricall connecting the two rails'ofthe track. ecircuit is divided into sections of dierent reL slstances, and at the terminals of the circuit are indicators, such as voltmeters, for deterV mining the resistance offered b the circuit to the passage of the current. iach section of the circuit has a fixed resistance different from the resistances of any other section. When the' circuit is completed through a particular section by the wheels and axle of a car or engine, by observing the indicator which registers the resistance of that particu lar section the location of the train can be determined from either end of the track.

The invention consists in the novel con struction, combination, and arrangementcf parts, 'such as will bel hereinafter fully de-i scribed, pointed out in the appended claims, v gdrawing. The figure of the drawing 1s a diagrammatic` view of an electrical signal system ern-'- bodying the invention.

'1 e railway-track A has one of its rails a electrically continuous from one end of the track to the other, the ends of the rail-sections bein bonded in any suitable manner,

as at a". he other rail a is divided b the insulating-breaks a into sections or b ocks B Bz B. Extending along the track are the electrical conductors C and D. The conductor C is connected at intervals with the sections or blocks B. B* B by the resistancecoils C C C, respectively, and the conductor D is also connected with the said block orsac- B2 seventy-five ohms, and

tions by the resistance-coils D D2 D, respec- 5 5 ductor C, which resistance is different from 6o the resistances of the other sections connected with such conducton. ,For an instance, the resistance of the section B through the conductor C to the left end of the system may be one hundred ohms,

the section B fift. ohms. Also each one of the sections or locks B B B, through its respective coil i D', D, or D, has a fixed resistance when theA circuit is' completed through the` conductor 7o D, which'resistance is different from the resistances of the other sections connected with the conductor D. For an instance, the resistance of the section B through the conductor D to thc'right of the system may be 75 fifty ohms, of the section B se'ventyfiveV ohms, and the section Bs one hundred ohms) Itis to be noted that the variations in the re' sistances of the members as they are grouped on either conductor C 0r D is considerable to 8o alicw `orfan minor chan es in the diiierent resistances that may be rought about by we therconditions andother causes. The di erentsresistances of theseveral sections may be established by any of the Well-known .8 5

methods of calibration.

At the opposite ends of the track A are the shunt-wound dynamos E and F, res ectively. in circuit with the shunt or field coi E of the dynamo E are the rail A and the conductor C, 9o

and in circuit with the shunt or field coil Ff of theV d amo F are the raii o and the conductor An electrif: bridge G connects the rail a with the rail a". Through the rails o a the bridge G, the conductors C D, and the re- 95 sistance-coils C C' C and D D Ds the shunt or field coils oi the two 'dynamos are connecta ed in series, so as to form one long shunt across the entire circuit. The electric bridge l of the section 65,

G forms a connection between the rails a and x ce a, so that the circuit of the eld-coils of the dynamos will always be closed. The resistance ofthe bridge is such, however, that but little current would ass through the lsame should the wheels and) connection between the two rails.

Interposed in the main circuits E and F of the dynamo; E and F, respectively, are the axle of a car make the :o5

voltmeters E3 and F3, respectively. As the field or shunt coil E of the dynamo E is connected with the conductor (l, the voltmeter Ff* will indicate the resistance offered to any current that mav pass through any one ofthe sections or blocks connected with said conductor C should a section or bIock be electrically connected with the rail ai. Likewise thc voltnieter F3 would indicate the resistance offered to an current that might pass through any one o the blocks or sections connected with the conductor I). As the resistance of each. section on either conductor is known, the particular section that may be in electrical connection with the rail a` can be ascertained by observing the resistance indicated by either' voltmeter. Owing to the completion of the circuit by the bridge G, there will be a constant flow of the current at a low voltage through the circuit Awhen there are no cars on the track. lThis will cause a slight delection ol' the needles of the vpltmeters at the ends of the circuit,and consequcntly it can always be determined if the circuit is -in working order. The oint at which the needles stand under suc conditions can be made the zero-point of the volt- Ineters. Should the needles drop below that point, they would indicate that the circuit ad been broken.

The operation of the system is asfollows: As shown in the drawing, the wheels and axle H are on the section B and form an electrical connection between the rails a and a2. The current Jfrom the dynamo E will pass from the conductor @,throu h the coil G', the rail a2, thc wh'eels and axle I, the rail d, and back to the dynamo. As the resistance of the section B' through the conductor C andthe intermediate connections is one hundred ohms, the voltmeter E3 measuring such a resistance will indicate to the observer at the left-h and terminal of the track that the train is on the said section B. Likewise with the voltmetcr FJ the observer at the right-hand terminal can also ascertain the position of the train. With the wheels and axle H electrically connectingV the rails a and a2 at section B the current from the dynamo F and the rail a will pass through the wheels and axle to the rail a?, thence through the coil D and the conductor D to the dynamo. The resistance of the section B through the conductor D and the intermediate connections with the dynamo F is fifty ohms. The voltmeter F3 showing such a measurement will indicate to the observer at the right-hand terminal that the train is on .section B. In thismanner the position of the train on any other one of the sections can beascertained.

While the hereinbefore-described embodiment of the invention is the preferred one, yet it can be departed from to a considerable extent without departing from the spiritA of the invention.

'Having described my invention, I cla1m- 1. In an electrical signal system, a railwaytrack, a source of electricity, a circuit con- 'i nected' with saidsource of electricity and extending along said track, bridging-coils interposed at intervals in said circuit to divide the same into blocks of different electrical resistanccs, means movable along said track and k o erating to close said circuit throu h said b ocks, and resistance-indicating mec anism operated by a current passing through said circuit.

2. In an electrical signal system, a railwaytrack, a source of electricity at each end of said track, a circuit common to both sources i of electricity and extending along said track, bridging-coils interposed at intervals in said circuit to divide the same into blocksof different electric resistances, means movable along-said track and operating to close said circuit through said blocks, and a resistancel indicating mechanism at each end of said track and' operated by a current passing throu hsaid circuit.

3. n an electrical signal system, a railwaytrack with one of its rails electrically continu- 1 ous and the other one divided by insulatingbreaks into blocks, a source of electricit connected with said continuous rail, a con uctor l extending along said track and connected with said source of electricity, bridging-coils connecting said conductor with the blocks of the divided rail` to form blocks of different said' track and operating to complete the cir- "fcuit between said rails, and a resistance-indieating mechanism operated by the current passing through the completed circuit.

4. In an electrical signal system, arailwaytrack with one of its rails electrically continuous and the other one divided by insulatingbreaks into sections, a source of electricity at said continuous rail,V separate conductors extending alongsaid track and respectivel connected with each source of electricity, D

of different electrical resistances, means movable along saidv track and operating to electrically connect said rails to complete the circuits through said conductors, and acresistance-indicating mechanism o erated by the current passing through eac of the completed circuits.

i 5. In an electrical signal system,arailwayi track, a dynamo, a circuit connected `with said dynamo and extending along said track,

bridging-eoils interposed at intervals in said i circuit to divide the same into blocks of difi ferent electrical resistances, means movable along said track and operating to close said circuit through said blocks, and a resistanceindicating mechanism connected with said dynamo.

electrical resistances, means movable alongl each end of said track and connected withridiging-coils connecting the sections of said i- Vvided rail with said conductors to form blocks 'IOO 6. In an electrical signal system, a railwaytrack with one of its rails electricaily continuous and the other one divided by insulat- 'Y ing-breaks into sections, a. d

Y amo at each end of said track with its fiel -coil connected with said electrically-continuous rail, sepa" rate conductors res ctively connected with the field-coil of eac dynamo and extending aiong said track, bridgin -coils connecti each of the sections of sai divided rail both conductors to form biocks of diere'nt electrical resistances, meansmovable alo said track and operating to compiete hot circuits, and resistance-indicating mechanisms res ectively connected with the main circuit o each dynamo.

S. In an electrical signal system, a railwaytrack, dynamos at opposite ends of sald track and having a circuit common to both,- bridgin -coils interposed in said circuit" to form b ocks ci diierent resistances, means movable on said track and operati to close said circuit through said blocks, an a resistance-indicating mechanism connected with each of said dynamos.

9.V In an electrical signal system, a railwaytrack, shuntwound dynamos at op Vosito ends of said track and having their s untcoils connected in series and extending across the entire circuit, bridging-coils interosed. in the circuit formed b the connection vetween the shunt-coils of t e dynamos and forminz blocks of different resistances, means movab c ou said track and'operatin to ciose said shunt-circuit through said bloc s, and a resistance-indicating mechanism operated by the current passing through the imain circuit ci each dynamo.

10. In an ,electrical si al system, a railway-track, a source of e ectricity, a circuit connected with said source of electricity and extending along said track, means for dividing said Kcircuit into blocks of different. electi'lcai rcsistances, means movable along said track and operating to close said circuit through said blocks, and resistance-indicating mechanism operated by a current passing through said circuit.

1L In an electrical signal system, a railway-track, a shunt-wound dynamo, a circuit connected with the shunt-coi of said dynamo and extending along said track, means for diri said circuit into biocks of dierent Y electrical resistances, means movable on said track and operating` to close said circuit through said blocks, and resistance-indicating mechanism operated by the current pass- 'Y ing through the main circuit or said dynamo.

12. In an electricai signal system, a rail- Way-track, a shunt-wound d connected with the sifiunt-eoV of said dynamo and extendmg-along said track, means movable on said track and operating to short-circuit said circuit, and resistance-indicating mechanism operated by the current passing through the main circuit of said dynamo."

13. In an electrical si al system, a railway-track, a source of e ectricity, a circuit connected with said source of electricity extending along said track and adapted to be short-circuited by an obstruction on said track, means for dividing said circuit into blocks of different electrical resistances, and resistance-indicating mechanism operated by a current passing through said circuit.

14. In an electrical signal system, a raiiway-track, a shunt-wound dynamo, a circuit extending alon said track and adapted to he short circuito by an obstruction on said track and connected with the shuntcoil of said dynamo, and resistance-indicating mechanism operatedr by the current passing thro ugh the main circuit of said d name.

In testimony whereof hereunto aiiix my signature in the presence of two witnesses.

`FRED LACROIX.

Witnesses:

CHAs. F. A. HUMMEL, JOHN U. MUELLER,

amo, a circuit 

